Amazon ACoS vs ROAS: What They Mean and How to Optimize Both

Q: What is a good ACoS on Amazon?

A "good" ACoS depends on your profit margin. Your break-even ACoS is your profit margin percentage — if your margin is 25%, your break-even ACoS is 25%. Target ACoS should be below your break-even. For most categories, sellers aim for 15–25% ACoS. Sellers in aggressive launch phases may accept higher ACoS temporarily to gain ranking.

Q: What is the difference between ACoS and TACoS?

ACoS (Advertising Cost of Sale) is calculated as ad spend divided by ad-attributed revenue only. TACoS (Total Advertising Cost of Sale) is ad spend divided by total revenue (ad + organic). TACoS gives a fuller picture because Amazon ads boost organic ranking, which generates sales not attributed to ads. A healthy TACoS is typically 5–15%.

Q: How do you calculate break-even ACoS?

Break-even ACoS equals your profit margin percentage. Formula: Break-even ACoS = (Sale Price − Total Costs) ÷ Sale Price × 100. If your sale price is $40 and your total non-ad costs (product, FBA fee, referral fee) are $28, your profit before ads is $12, making break-even ACoS = $12 ÷ $40 = 30%. Any ACoS below 30% means ads are profitable.

Q: Is ROAS the same as ACoS?

ACoS and ROAS measure the same relationship from opposite angles. ACoS = Ad Spend ÷ Ad Revenue (lower is better). ROAS = Ad Revenue ÷ Ad Spend (higher is better). They are mathematical inverses: ROAS = 1 ÷ ACoS. An ACoS of 25% equals a ROAS of 4.0. An ACoS of 20% equals a ROAS of 5.0.

Amazon sellers track two advertising metrics more than any others: ACoS and ROAS. They measure the same thing — how efficiently your ad spend generates revenue — but from opposite angles. Confusing them leads to wrong conclusions. This guide explains what each metric means, how to calculate your break-even, what healthy numbers look like, and when to use TACoS instead.

ACoS: Advertising Cost of Sale

ACoS (Advertising Cost of Sale) is the percentage of ad-attributed revenue you spent on advertising.

ACoS = (Ad Spend ÷ Ad Revenue) × 100

Example: You spend $200 on Sponsored Products ads. Those ads generate $1,000 in sales. Your ACoS is 20%.

Lower ACoS = more efficient ads. An ACoS of 15% means you spent $15 to generate $100 in revenue. An ACoS of 40% means you spent $40 for the same $100 in revenue.

ROAS: Return on Ad Spend

ROAS (Return on Ad Spend) is the revenue you earn for every dollar spent on advertising.

ROAS = Ad Revenue ÷ Ad Spend

Using the same example: $1,000 revenue ÷ $200 spend = ROAS of 5.0. You earned $5 for every $1 spent on ads.

Higher ROAS = more efficient ads.

ACoS and ROAS Are the Same Metric

ACoS and ROAS are mathematical inverses of each other:

ROAS = 1 ÷ (ACoS / 100)
ACoS = (1 ÷ ROAS) × 100

ACoS	ROAS	Meaning
10%	10.0	Very efficient
15%	6.7	Strong
20%	5.0	Good
25%	4.0	Acceptable for many products
33%	3.0	Marginal — check your break-even
50%	2.0	Likely unprofitable unless high-margin
100%	1.0	Break-even on ad spend only (always a loss)

Amazon Seller Central shows ACoS by default. Google Ads and Meta default to ROAS. The metric you see depends on the platform — not on some fundamental difference in what's being measured.

Break-Even ACoS: The Number That Actually Matters

Knowing your ACoS is useless without knowing your break-even ACoS — the ACoS at which your ads exactly break even. Below break-even = profitable ads. Above break-even = you're losing money on ads.

Break-Even ACoS = Profit Margin Before Ads
                = (Sale Price − Non-Ad Costs) ÷ Sale Price × 100

Non-ad costs include: product cost, FBA fulfillment fee, Amazon referral fee, shipping to Amazon, and any other fixed per-unit costs.

Example calculation for a $45 product in Home & Kitchen:

Item	Amount
Sale price	$45.00
Product cost (landed)	$12.00
Amazon referral fee (15%)	$6.75
FBA fulfillment fee (large std, 12 oz)	$4.11
Other costs (returns, storage)	$0.80
Profit before ads	$21.34
Break-even ACoS	$21.34 ÷ $45 = 47.4%

With a 47.4% break-even ACoS, this product has substantial room to run ads profitably. A seller targeting 25% ACoS would generate ($21.34 − $11.25) = $10.09 profit per unit after ads.

Calculate your break-even ACoS and ROAS

Enter your ad spend and revenue to see ACoS, ROAS, and TACoS side by side.

Open ACoS Calculator →

TACoS: The Metric That Shows the Full Picture

ACoS only counts sales attributed to ads. But Amazon ads do something important beyond direct sales: they boost your organic ranking, which generates organic sales that aren't attributed to your ad campaigns.

TACoS (Total Advertising Cost of Sale) captures this:

TACoS = Ad Spend ÷ Total Revenue (ad + organic) × 100

Example: You spend $500 on ads. Ads generate $2,000 in attributed sales. Your product also generates $3,000 in organic sales (boosted by ad-driven ranking). Total revenue = $5,000.

ACoS = $500 ÷ $2,000 = 25%
TACoS = $500 ÷ $5,000 = 10%

The TACoS tells the real story: you're spending 10% of total revenue on ads, which is quite efficient even if the ACoS looks high.

When a product's TACoS decreases over time while maintaining sales volume, it usually means organic ranking is improving and the product is becoming less dependent on ads — a very healthy signal.

ACoS Benchmarks by Strategy

Strategy	Target ACoS	When to Use
Profit maximization	10–20%	Established products with strong organic rank
Balanced growth	20–30%	Products with good reviews, scaling phase
Aggressive launch	30–50%+	New listings, building rank and reviews
Break-even (brand awareness)	= profit margin %	New product in competitive category

There is no universal "good ACoS." The number must be evaluated against your specific profit margin. A 30% ACoS on a 40% margin product is profitable. A 30% ACoS on a 20% margin product is losing money.

How to Improve Your ACoS

Negative keyword sculpting: Add negative keywords for search terms that spend budget without converting. This is usually the fastest way to drop ACoS without reducing sales volume.
Bid adjustments by placement: Amazon lets you adjust bids for top-of-search, rest-of-search, and product pages. High-converting placements deserve higher bids; low-converting ones should be reduced.
Improve listing conversion rate: If your listing converts poorly, no bid strategy will fix your ACoS. Better main images, cleaner title, more detailed bullet points, and more reviews all improve conversion rate, which directly lowers ACoS.
Harvest keywords from Auto campaigns: Run auto campaigns to discover converting search terms, then move those terms into manual exact-match campaigns with controlled bids.
Price competitively: If your price is higher than alternatives, conversion rate suffers and ACoS rises. Price testing can reveal the sweet spot between margin and conversion.

Frequently Asked Questions

What is a good ACoS on Amazon?

A "good" ACoS is any number below your break-even ACoS (which equals your profit margin percentage). Most profitable sellers target 15–25% ACoS. During product launches, accepting ACoS at or above break-even is common to build ranking and reviews.

What is the difference between ACoS and TACoS?

ACoS is ad spend divided by ad-attributed revenue. TACoS is ad spend divided by total revenue (ad + organic). TACoS gives a fuller picture because it accounts for the organic ranking boost that ads provide. A healthy TACoS is typically 5–15%.

How do you calculate break-even ACoS?

Break-even ACoS = profit margin before ads. Subtract all non-ad costs (product, FBA fees, referral fee) from sale price, then divide by sale price. Example: ($45 sale − $23.66 costs) ÷ $45 = 47.4% break-even ACoS.

Is ROAS the same as ACoS?

Yes — they measure the same thing from opposite directions. ACoS = Ad Spend ÷ Revenue (lower is better). ROAS = Revenue ÷ Ad Spend (higher is better). ROAS = 1 ÷ ACoS. A 25% ACoS equals a ROAS of 4.0.